From the earliest conceptions of movable vehicles such as automobiles and the like, the need has arisen for an effective means for clearing or wiping the windshield when the vehicle is operated in rain, snow or, other precipitation. The general development of such windshield wipers developed from early hand operated units to the later developed electrically powered windshield wipers. While various configurations of windshield wipers have been attempted in the past, generally all present day vehicles utilize wiper systems in which one or more wiper blades are moved back and forth across the windshield in an arc-shaped path by a pivotally supported motor driven wiper arm. Because the great majority of vehicle windshields are generally rectangular in shape, the arc-shaped path of the windshield wiper blades service a limited portion of the windshield area leaving other portions unwiped. In attempts to minimize the unwiped portions of the windshield surfaces practitioners in the art have utilized pluralities of wiper blades having overlapped arc-shaped travel paths. While this has provided some improvement and reduced the unwiped area of the vehicle windshield, there remain significant windshield areas which are unattended and thus pose a potential visual impediment and hazard to the vehicle operator. In addition to the problems arising from the use of rectangular shaped windshields, designers of vehicles are further motivated by aesthetic and structural considerations to provide windshields which are curved. The curved aspect of windshields further exacerbates the problems of covering the windshield area with wiper systems having arced travel paths.
A number of designers have recognized the effectiveness of providing windshield wipers which move one or more wiper blades in a linear or lateral travel path across the windshield. This system is inherently advantageous in terms of minimizing unserviced areas of the VEHICLE windshield. However, practical attempts to produce lateral travel windshield wipers have been frustrated by the complexities and difficulties of the drive systems used to move the wiper blade back and forth across the windshield surface. As a result, most vehicle manufacturers have been unsuccessful in producing a practical lateral travel wiper drive mechanism and have settled for the simpler mechanisms used to drive the arced path type wipers.
U.S. Pat. No. 934,007 issued to Null sets forth a WINDOW CLEANER in which a blade support is positioned beneath a windshield and receives a slide member thereon. The slide member supports a vertical wiper arm which in turn supports a wiper blade. A flexible belt mechanism is supported beneath the blade support and is driven by a crank assembly. The crank motion of the crank assembly is converted to linear motion of the wiper arm to move the blade back and forth across the windshield.
U.S. Pat. No. 1,665,570 issued to Waters sets forth a ELECTRIC WINDSHIELD WIPER in which a motor driven slide is moved back and forth across the upper portion of a vehicle windshield. A belt drive is operative upon the slide and a downwardly extending wiper arm is supported by the slide and in turn supports a wiper blade.
U.S. Pat. No. 1,720,832 issued to Gibson sets forth a WINDSHIELD WIPER in which an endless band defines a plurality of perforations and is driven by an electric motor drive. A slide member is coupled to the endless band which supports a downwardly extending wiper arm and wiper assembly. The electric motor drives the endless band to move the slide and wiper assembly across the windshield.
U.S. Pat. No. 1,748,055 issued to Brown, et al. sets forth an WINDSHIELD WIPER in which a slide track is positioned within an endless belt or chain drive assembly, A slide member is movable upon the slide track and supports a windshield wiper. A pivotal coupling arm is secured to the endless belt or chain and converts the single direction motion of the endless belt or chain to a reciprocating slide motion for the wiper arm supported by the slide.
U.S. Pat. No. 1,846,588 issued to Dudley sets forth a WINDSCREEN WIPER in which a pair of wiper arms are supported in a sliding track and driven laterally by an endless belt. The arms are spaced apart upon the belt and are moved in unison back and forth across the windshield.
U.S. Pat. No. 2,063,055 issued to Shaw sets forth a WINDSHIELD WIPER which utilizes a dual system of endless belts and slide members coupled thereto to provide a pair of laterally moving windshield wipers upon a common windshield.
U.S. Pat. No. 2,648,087 issued to Kiker, Jr. sets forth a WINDSHIELD WIPER in which an endless belt or cable is movably supported in a track system which encircles a generally rectangular windshield. A pair of slide members support a vertical wiper arm and means are provided for coupling the slide members to the moving belt to provide lateral travel thereof.
U.S. Pat. No. 3,505,702 issued to Omlie, et al. sets forth a WINDOW WIPING APPARATUS HAVING A LINEARLY MOVABLE WIPER in which a lateral travel wiper assembly is supported on the rear windshield of a vehicle. The Wiper assembly includes an endless belt drive system and movable slide supporting a vertical wiper arm. The wiper arm is movable to an alternate horizontal position for storage.
U.S. Pat. No. 3,032,797 issued to Presser sets forth a WINDOW CLEANING DEVICE for simultaneously and automatically cleaning the opposite surfaces of a window pane. The apparatus includes a wetting or moisturizing means coactive with the window wiping elements. A pair of wiping elements or blades are positioned on opposite sides of the window and moved back and forth as the window is cleaned.
U.S. Pat. No. 2,944,276 also issued to Presser sets forth a WINDOW CLEANING DEVICE in which a motor driven continuous belt moves a wiper blade upon a planar window surface. In its preferred form, a pair of track supports and endless belts move a pair of oppositely positioned carriages having a wiper blade secured therebetween.
Additional patents have been found generally related to apparatus such as that utilized in various reciprocating machine systems such as U.S. Pat. Nos. 2,433,180; 3,693,773; 3,530,268; and 4,441,692. In further addition, several foreign patents have been found which are directed to similar objectives to the present invention which include British Patent 2,085,713, French Patent 1,067,491; British Patent 540,427; German Patent 1,093,236; and Japanese Patent 59-29548.
While the foregoing described prior art devices are representative of the attempts to produce a practical lateral travel windshield wiper, their mechanisms have proven to be generally cumbersome, expensive and often unreliable. There remains, therefore, a need in the art for an effective, efficient and reliable lateral travel windshield wiper system.